\section{Implementation}
\label{sec:implementation}

Generally, CCA check duration must be longer than the ACK delay to avoid false negatives which may decrease the system performance.
CCA check duration is 11.5 ms in default (with ACK delay 10 ms) and 4.5 ms under reduced ACK delay in ADEP \cite{bib:IPSN13EnergyLPL} (with ACK delay 2.8ms).
IALPL adopts the reduced ACK delay setting as ADEP.
The interval in preamble is 2.8ms and the duration of CCA check is 4.5 ms.
To be fair, we also improve the default Box-MAC-2 by reducing CCA check to 2.9 ms and a preamble interval to 2.8 ms.
IALPL does the RSSI sampling with the same time ADEP does energy detection, which is 2.9 ms, i.e., 90 samples under the sampling rate of IALPL. 

